1. Field of the Invention
The present invention relates to an apparatus for defrosting the evaporator coil of a conventional refrigeration unit, more particularly, the invention relates to an apparatus for applying heat to the refrigerating fluid in the heat exchanger during the defrosting cycle.
2. Prior Art
Conventional apparatus utilize a heat exchanging process during the defrosting cycle wherein the refrigerating fluid is fed under pressure to a cooler by means of a compressor so as to defrost the inside of the cooler. After expanding and evaporating the refrigerating fluid by circulating the fluid to the heat exchanger and heating the fluid by water circulation in heat exchange relationship with the fluid, the gas is intended to be vaporized so that no liquid will pass back through the compressor. A difficulty which arises in such prior art devices is that in the heat exchange process the refrigerating fluid is cooled by the circulated water in a heat exchange relationship with the fluid in such a manner that it is not completely efficient in the expansion and evaporaton of the refrigerating fluid and therefore, the fluid is incompletely evaporated leaving some of the fluid in a liquid state instead of entirely in a gaseous state as it is passed through the compressor, causing it to damage the compressor or substantially reduce the efficiency thereof.